https://cxc.cfa.harvard.edu/mta/MSID_Trends/Obaheaters/Oobthr39/oobthr39_min_long_sun_angle.html
OOBTHR39 vs Sun Angle
vssunangle
https://cxc.cfa.harvard.edu/mta/MSID_Trends/Obaheaters/Oobthr39/oobthr39_max_long_sun_angle.html
OOBTHR39 vs Sun Angle
vssunangle